cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-4 of 4 results.

A138995 First differences of Frobenius numbers for 4 successive numbers A138984.

Original entry on oeis.org

1, 1, 6, 2, 2, 10, 3, 3, 14, 4, 4, 18, 5, 5, 22, 6, 6, 26, 7, 7, 30, 8, 8, 34, 9, 9, 38, 10, 10, 42, 11, 11, 46, 12, 12, 50, 13, 13, 54, 14, 14, 58, 15, 15, 62, 16, 16, 66, 17, 17, 70, 18, 18, 74, 19, 19, 78, 20, 20, 82, 21, 21, 86, 22, 22, 90, 23, 23, 94, 24, 24, 98, 25, 25, 102, 26
Offset: 1

Views

Author

Artur Jasinski, Apr 05 2008

Keywords

Comments

For first differences of Frobenius numbers for 2 successive numbers see A005843
For first differences of Frobenius numbers for 3 successive numbers see A014682
For first differences of Frobenius numbers for 4 successive numbers see A138995
For first differences of Frobenius numbers for 5 successive numbers see A138996
For first differences of Frobenius numbers for 6 successive numbers see A138997
For first differences of Frobenius numbers for 7 successive numbers see A138998
For first differences of Frobenius numbers for 8 successive numbers see A138999

Crossrefs

Programs

  • Mathematica
    a = {}; Do[AppendTo[a, FrobeniusNumber[{n + 1, n + 2, n + 3, n + 4}]], {n, 1, 100}]; Differences[a]
    LinearRecurrence[{0, 0, 2, 0, 0, -1}, {1, 1, 6, 2, 2, 10},50] (* G. C. Greubel, Feb 18 2017 *)
    Differences[Table[FrobeniusNumber[Range[n,n+3]],{n,2,100}]] (* Harvey P. Dale, Dec 22 2018 *)
  • PARI
    x='x+O('x^50); Vec(-x*(2*x^5-6*x^2-x-1) / ((x-1)^2*(x^2+x+1)^2)) \\ G. C. Greubel, Feb 18 2017

Formula

a(n) = A138984(n+1) - A138984(n).
a(n) = 2*a(n-3) - a(n-6). - R. J. Mathar, Apr 20 2008
a(n) = (1/3)*x(mod(n,3))*mod(n,3)-(1/3)*n*x(mod(n,3))+(1/3)*n*x(3+mod(n,3))+x(mod(n,3))-(1/3)*mod(n,3)*x(3+mod(n,3)). - Alexander R. Povolotsky, Apr 20 2008
G.f.: -x*(2*x^5-6*x^2-x-1) / ((x-1)^2*(x^2+x+1)^2). - Colin Barker, Dec 13 2012

A138997 First differences of Frobenius numbers for 6 successive numbers A138986.

Original entry on oeis.org

1, 1, 1, 1, 8, 2, 2, 2, 2, 14, 3, 3, 3, 3, 20, 4, 4, 4, 4, 26, 5, 5, 5, 5, 32, 6, 6, 6, 6, 38, 7, 7, 7, 7, 44, 8, 8, 8, 8, 50, 9, 9, 9, 9, 56, 10, 10, 10, 10, 62, 11, 11, 11, 11, 68, 12, 12, 12, 12, 74, 13, 13, 13, 13, 80, 14, 14, 14, 14, 86, 15, 15, 15, 15, 92, 16, 16, 16, 16, 98, 17, 17
Offset: 1

Views

Author

Artur Jasinski, Apr 05 2008

Keywords

Comments

For first differences of Frobenius numbers for 2 successive numbers see A005843
For first differences of Frobenius numbers for 3 successive numbers see A014682
For first differences of Frobenius numbers for 4 successive numbers see A138995
For first differences of Frobenius numbers for 5 successive numbers see A138996
For first differences of Frobenius numbers for 6 successive numbers see A138997
For first differences of Frobenius numbers for 7 successive numbers see A138998
For first differences of Frobenius numbers for 8 successive numbers see A138999

Crossrefs

Programs

  • Mathematica
    a = {}; Do[AppendTo[a, FrobeniusNumber[{n + 1, n + 2, n + 3, n + 4, n + 5, n + 6}]], {n, 1, 100}]; Differences[a]
    LinearRecurrence[{0, 0, 0, 0, 2, 0, 0, 0, 0, -1}, {1, 1, 1, 1, 8, 2,
      2, 2, 2, 14}, 50] (* G. C. Greubel, Feb 18 2017 *)
    Differences[Table[FrobeniusNumber[Range[n,n+5]],{n,2,90}]] (* Harvey P. Dale, Dec 18 2023 *)
  • PARI
    x='x + O('x^50); Vec(-(-1-x-x^2-x^3-8*x^4+2*x^9)/((x-1)^2*(x^4+x^3+x^2+x+1)^2)) \\ G. C. Greubel, Feb 18 2017

Formula

a(n) = A138986(n+1) - A138986(n).
O.g.f.= -(-1-x-x^2-x^3-8*x^4+2*x^9)/((x-1)^2*(x^4+x^3+x^2+x+1)^2). - R. J. Mathar, Apr 20 2008
a(n) = 2*a(n-5) - a(n-10). - R. J. Mathar, Apr 20 2008
a(n)= (1/5)*n*x(5+mod(n,5))-(1/5)*mod(n,5)*x(5+mod(n,5))+x(mod(n,5))-(1/5)*n*x(mod(n,5))+(1/5) *mod(n,5)*x(mod(n,5)). - Alexander R. Povolotsky, Apr 20 2008

A138999 First differences of Frobenius numbers for 8 successive numbers A138988.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 10, 2, 2, 2, 2, 2, 2, 18, 3, 3, 3, 3, 3, 3, 26, 4, 4, 4, 4, 4, 4, 34, 5, 5, 5, 5, 5, 5, 42, 6, 6, 6, 6, 6, 6, 50, 7, 7, 7, 7, 7, 7, 58, 8, 8, 8, 8, 8, 8, 66, 9, 9, 9, 9, 9, 9, 74, 10, 10, 10, 10, 10, 10, 82, 11, 11, 11, 11, 11, 11, 90, 12, 12, 12, 12, 12, 12, 98, 13, 13, 13, 13
Offset: 1

Views

Author

Artur Jasinski, Apr 05 2008

Keywords

Comments

For first differences of Frobenius numbers for 2 successive numbers see A005843
For first differences of Frobenius numbers for 3 successive numbers see A014682
For first differences of Frobenius numbers for 4 successive numbers see A138995
For first differences of Frobenius numbers for 5 successive numbers see A138996
For first differences of Frobenius numbers for 6 successive numbers see A138997
For first differences of Frobenius numbers for 7 successive numbers see A138998
For first differences of Frobenius numbers for 8 successive numbers see A138999

Crossrefs

Programs

  • Mathematica
    a = {}; Do[AppendTo[a, FrobeniusNumber[{n + 1, n + 2, n + 3, n + 4, n + 5, n + 6, n + 7, n + 8}]], {n, 1, 100}]; Differences[a]
    Differences[Table[FrobeniusNumber[Range[n,n+7]],{n,2,90}]] (* Harvey P. Dale, Oct 02 2011 *)

Formula

a(n) = A138988(n+1) - A138988(n).
From R. J. Mathar, Apr 20 2008: (Start)
G.f.: -(-1-x-x^2-x^3-x^4-x^5-10*x^6+2*x^13)/((x-1)^2*(x^6+x^5+x^4+x^3+x^2+x+1)^2).
a(n) = 2*a(n-7) - a(n-14).
(End)
a(n) = -(1/7)*mod(n,7)*x(7+mod(n,7))+(1/7)*mod(n,7)*x(mod(n,7))+x(mod(n,7))-(1/7)*n *x(mod(n,7))+(1/7)*n*x(7+mod(n,7)). - Alexander R. Povolotsky, Apr 20 2008

A151898 First differences of Frobenius numbers for 7 successive numbers A138987.

Original entry on oeis.org

1, 1, 1, 1, 1, 9, 2, 2, 2, 2, 2, 16, 3, 3, 3, 3, 3, 23, 4, 4, 4, 4, 4, 30, 5, 5, 5, 5, 5, 37, 6, 6, 6, 6, 6, 44, 7, 7, 7, 7, 7, 51, 8, 8, 8, 8, 8, 58, 9, 9, 9, 9, 9, 65, 10, 10, 10, 10, 10, 72, 11, 11, 11, 11, 11, 79, 12, 12, 12, 12, 12, 86, 13, 13, 13, 13, 13, 93, 14, 14, 14, 14, 14, 100, 15
Offset: 1

Views

Author

Artur Jasinski, Apr 05 2008

Keywords

Comments

First differences of Frobenius numbers for 2 successive numbers see A005843
First differences of Frobenius numbers for 3 successive numbers see A014682
First differences of Frobenius numbers for 4 successive numbers see A138995
First differences of Frobenius numbers for 5 successive numbers see A138996
First differences of Frobenius numbers for 6 successive numbers see A138997
First differences of Frobenius numbers for 7 successive numbers see A151898
First differences of Frobenius numbers for 8 successive numbers see A138999

Crossrefs

Programs

  • Mathematica
    a = {}; Do[AppendTo[a, FrobeniusNumber[{n + 1, n + 2, n + 3, n + 4, n + 5, n + 6, n + 7}]], {n, 1, 100}]; Differences[a]
    Differences[Table[FrobeniusNumber[Range[n,n+6]],{n,2,90}]] (* or *) LinearRecurrence[ {0,0,0,0,0,2,0,0,0,0,0,-1},{1,1,1,1,1,9,2,2,2,2,2,16},90] (* Harvey P. Dale, Jul 26 2024 *)

Formula

a(n) = A138987(n+1)-A138987(n).
G.f.: -x*(2*x^11-9*x^5-x^4-x^3-x^2-x-1) / ((x-1)^2*(x+1)^2*(x^2-x+1)^2*(x^2+x+1)^2). [Colin Barker, Dec 13 2012]
Showing 1-4 of 4 results.